IOS Example of initWithCGColor - ios

Question

I give in, this is taking too long and I can't find the answer listed anywhere.
In the Framework Reference for UIColor there is a function initWithCGColor. How do you use this? Can someone please help with example? I am looking to initialize a color to a specific value!
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIColor_Class/index.html#//apple_ref/occ/instm/UIColor/initWithCGColor:

Answer 1

CGColorRef is a class used for drawing using Core graphics. If you want to initialise an UIColorobject with a specific RGB value, use
- initWithRed:green:blue:alpha:
Swift
let color = UIColor(red: 59/255.0, green: 136/255.0, blue: 195/255.0, alpha: 1)
Objective-C
UIColor * color = [UIColor colorWithRed:59/255.0f green:136/255.0f blue:195/255.0f alpha:1];
For helping purposes, I add some useful extension/macro for UIColor in order to initialise objects without having to consider the division by 255.
I am not the creator of this code but a grateful user who wants to share some time-saving code :
Swift
public extension UIColor{
class func initRGBA(r r:CGFloat, g:CGFloat, b:CGFloat, a:CGFloat) -> UIColor
{
return UIColor(red:r/255, green: g/255, blue: b/255, alpha: a)
}
class func initRGB(r r:CGFloat, g:CGFloat, b:CGFloat) -> UIColor
{
return UIColor.initRGBA(r:r, g:g, b:b, a:1)
}
class func initRGBGRAY(gray:CGFloat) -> UIColor
{
return UIColor.initRGBA(r:gray, g:gray, b:gray, a:1)
}
convenience init(rgb: UInt) {
self.init(
red: CGFloat((rgb & 0xFF0000) >> 16) / 255.0,
green: CGFloat((rgb & 0x00FF00) >> 8) / 255.0,
blue: CGFloat(rgb & 0x0000FF) / 255.0,
alpha: CGFloat(1.0)
)
}
}
/// Let's initialize a color
let color = UIColor.initRGB(r: 24, g: 80, b: 145)
Objective-C
#define RGBCOLOR(r,g,b) [UIColor colorWithRed:(r)/255.0f green:(g)/255.0f blue:(b)/255.0f alpha:1]
#define RGBACOLOR(r,g,b,a) [UIColor colorWithRed:(r)/255.0f green:(g)/255.0f blue:(b)/255.0f alpha:(a)]
#define RGBGRAYCOLOR(g) [UIColor colorWithRed:(g)/255.0f green:(g)/255.0f blue:(g)/255.0f alpha:1]
/// Let's initialize a color
UIColor * color = RGBCOLOR(87, 99, 132);